Rearview mirrors have been included as standard equipment inside conventional automobiles and related vehicles for decades. Such apparatus provides an invaluable safety function in that the operator may, at will, ascertain the traffic condition behind him through a minor eye movement. Outside rearview mirrors have also been provided which facilitate viewing the roadway traffic beside or diagonally behind the operator's vehicle out of view of conventional "inside" mirrors. In the not too distant past, inside rearview mirrors have included "day-night" features which permit the operator to select the most advantageous viewing configuration for the time of day. The configuration adjustments have commonly been centered in the mirror reflective surfaces.
Prior art day-night mirrors, used inside automobiles, at one time included two mirrors placed back-to-back and pivoted to provide either a bright image reflection for daytime viewing or a darkened reflection for nighttime viewing purposes. It has been shown, however, that the function of reaching up and manually flipping the mirror from day to night position also necessitates an inconvenient resetting of the viewing pitch and yaw angle. Such requisite adjustments have limited the effectiveness of these mirrors in that the operator often decides to leave it in the day position rather than readjust it.
More recent prior art day-night mirrors for inside the automobile include a bright image mirror that has a plain see-through glass disposed in front of it. The bright image surface is for daytime viewing and when it is tilted up, at night, so that it reflects the darkened interior of the car, the plain glass surface provides a rearview image. In this manner, only the residual image appears on the see-through glass and the harsh headlights of adjacent traffic are reflected off the tilted bright image surface and upwardly above the operator. The apparatus providing such an adjustability function is basic. Fixed stops and detent means establish the end positions for each day night adjustment. Viewing pitch and yaw angles are adjusted by orienting the mirror housing and no secondary adjustments for viewing angles are necessary when switching from night to day, or vice versa. Such mirrors have thus found wide spread acceptance in the automotive industry.
The standard see-through glass apparatus of the inside mirror will not work as an outside rearview mirror. The reflection of street lights, neon signs, lighted buildings nad the like would be picked up by the tilted mirror surface. This would produce a dangerous double image to the operator. Therefore, double sided mirrors utilized for outside rearview mirrors which eliminate double reflection have been the subject of development efforts. The main problem with such apparatus is the remote adjustability of such mirrors between day and night positions, as discussed above. Certain prior art structures have addressed this problem by providing multiple unit cable linkages between the mirror and a central unit on the automobile door adjacent the operator. One such remote control device is shown and described in U.S. Pat. No. 3,650,606, issued to Andrew J. Van Voord in 1972. This mirror control device disclosed therein includes a four wire cable adapted for turning the mirror supporting member right or left and up and down. In combination, these functions allow the operator to both flip the mirror 180.degree. and adjust it at each end of the flip for proper viewing angles.
Other prior art remote control structures for outside rearview mirrors have included prismatical mirrors, fluid mirrors and related double sided mirrors. Each mirror structure generally includes a double control for manually changing the pitch and yaw viewing angle and day-night configuration. Beside being inherentaly complicated and concommitantly expensive, several of these structures exhibit a common adjustability malady. Generally each flip style mirror must be adjusted at the end of the flip for the proper viewing angle. Although controls are provided for remote adjustment, again such functions require manual effort and pose an inconvenience for the operator.
It would be an advantage therefore to provide a day-night outside rearview mirror, the day-night configuration of which can be obtained without the necessity of readjusting the viewing angle thereof. It is therefore the purpose of the present invention to overcome the problems of the prior art devices by therein controlling the actuation of a double sided mirror wherein it can be flipped from day to night viewing positions while maintaining the same viewing angle at each end. A mechanical servo is therefore provided for segregating mirror adjust signals from an input bezel into flip and pitch adjustments transmissions. The servo is constructed to permit only one mode of pitch signal at a time, therein retaining the configuration of the other. In this manner, the servo functions as a remote control transducer and mirror position memory bank for the convenience of the operator.